Concrete Calculator

Calculate cubic yards of concrete needed for slabs, footings, driveways, and walkways. Get accurate concrete estimates with bag counts and cost projections.

Calculator Inputs
Your Results

Enter your values and click Calculate to see results

Accurate Concrete Estimation

Precise Volume

Calculate exact cubic yards needed based on length, width, and thickness measurements.

Bag Counts

Get the exact number of 80lb or 60lb concrete bags needed for your project.

Cost Comparison

Compare costs between ready-mix delivery and bagged concrete to find the best option.

Concrete Volume Formula

The formula calculation is standard for this mathematical operation.

Cubic\ Yards = \frac{Length \times Width \times Thickness_{feet}}{27} \times Waste\ Factor

Variables Explained:

Length
Length of area in feet
Width
Width of area in feet
Thickness
Thickness in feet (inches ÷ 12)
27
Conversion factor (27 cubic feet = 1 cubic yard)
Waste Factor
Overage for waste (typically 5-10%)

Worked Examples

Standard Driveway
20×12 ft driveway, 4 inches thick with 5% waste

Inputs:

project Type:
slab
length:
20
width:
12
thickness:
4
waste Factor:
1.05

Result:

3.11 cubic yards needed

Patio Slab
15×10 ft patio, 4 inches thick with 5% waste

Inputs:

project Type:
slab
length:
15
width:
10
thickness:
4
waste Factor:
1.05

Result:

1.94 cubic yards needed

Foundation Footing
30×2 ft footing, 8 inches thick with 10% waste

Inputs:

project Type:
footing
length:
30
width:
2
thickness:
8
waste Factor:
1.10

Result:

4.07 cubic yards needed

Frequently Asked Questions